The pyrolysis of 1-dodecylpyrene (DDP), which can serve as a chemical model of the alklaromatic structural elements in heavy hydrocarbon resources, is modeled using a detailed free-radical reaction mechanism and estimated rate constants for the elementary steps, This mechanism differs from previous work in that it includes hydrogen-transfer reactions from 4,5-dihydropyrene and 1-(1-dodecenyl)pyrene, which are products of DDP pyrolysis, to DDP. The model is validated by comparing its predictions with experimental results for the effects of time, temperature, and initial concentration on the kinetics of DDP disappearance and product formation. Removing the radical hydrogen-transfer (RHT) steps from the validated model. revealed that the more conventional hydrogen-transfer steps of reverse radical disproportionation and H atom addition are insufficient to describe all of the experimental observations. Moreover, varying the resonance stabilization energy, the C-H bond dissociation energies for hydropyrenyl radicals, and the additional stabilization energy attributed to the double bond in 1-(1-dodecenyl)pyrene cannot bring the results of the model without RHT into agreement with experimental observations. Including radical hydrogen transfer or phenomenologically similar steps appears to be necessary to model DDP pyrolysis.
